Use of composite materials as structural components for the marine and aerospace industries dates back to the 1940's. Typically, the composite materials are polyester or epoxy resin based. While choice of a particular composite is dictated by application, generally any one of the composites is the optimal choice with respect to strength, weight, cost, etc., when compared with other materials (e.g., metal, wood, etc.).
Unfortunately, experience has shown that most organic matrix materials, particularly the conventional polyester and epoxy types, support combustion and generate large quantities of smoke when burning. It has thus become necessary to place restrictions on using such materials in certain applications until such time that these materials can offer improved fire performance. Towards this end, it has been proposed that phenolic laminates be used as a sacrificial fire barrier formed on the individual, composite material structure components. Phenolic laminates, when compared with the polyester and epoxy resins, exhibit higher ignition resistance, low flammability and generate far lesser amounts of smoke. Phenolic laminates, however, possess poor bonding properties due to their higher void content. Since the laminates are made from continuous roving, debonding causes large portions of laminate ply to peel and, subsequently, fall off. Thus, the phenolic laminates frequently break up and fall off the structural component to which they have been bonded. Furthermore, since the phenolic laminates are formed on each individual structural component, fire protection discontinuities are formed between assembled components. Finally, high labor cost is associated with the laminated components since the laminates are typically hand laid.